单词birch family
un.: 桦木科
网络: 桦木属
桦木科
of or pertaining to or characteristic of trees of the birch family.
属于、关于或具有桦树科树木特征。
Pollen from an alder (a tree of the birch family) .
桤木的花粉，桦树科的一种。
Alder trees belong to the birch family.
赤杨属于桦木科。
Alder: tree of the birch family, usu growing in marshy places
桤木（桦木科，通常生长于沼泽地带）。